Surgical instrument with sensor

ABSTRACT

A surgical instrument includes a housing, a shaft extending distally from the housing, an end effector disposed at a distal end of the shaft, an actuator operably coupled to the housing, an actuation assembly, and a sensor module. The actuation assembly extends through the housing and the shaft and includes a distal end operably coupled to the end effector or a component associated therewith, a proximal end operably coupled to the actuator, and a spring. Actuation of the actuator manipulates the end effector or deploys the component relative thereto. The sensor module is disposed within the housing and configured to sense a property of the spring indicative of an amount the spring has been compressed. The sensor module is further configured, based upon the sensed property, to determine a condition of the end effector or the relative position of the component.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent applicationSer. No. 16/899,678, filed on Jun. 12, 2020, which is a continuation ofU.S. patent application Ser. No. 15/401,227, filed on Jan. 9, 2017, nowU.S. Pat. No. 10,695,123, which claims the benefit of and priority toU.S. Provisional Application No. 62/288,962, filed on Jan. 29, 2016. Theentire contents of each of which are hereby incorporated herein byreference.

BACKGROUND 1. Technical Field

The present disclosure relates generally to the field of surgicalinstruments. In particular, the disclosure relates to a surgicalinstrument including a sensor(s) enabling the determination of theposition and/or force associated with components of the surgicalinstrument.

2. Background of Related Art

Surgical instruments such as electrosurgical forceps are commonly usedin open and endoscopic surgical procedures to treat tissue, e.g.,coagulate, cauterize, and/or seal tissue. Electrosurgical forcepstypically include a pair of jaw members that can be manipulated to grasptargeted tissue. More specifically, the jaw members may be approximatedto apply a mechanical clamping force to the tissue, and are associatedwith at least one electrode to permit the delivery of electrosurgicalenergy to the tissue.

The combination of mechanical clamping force and electrosurgical energyhas been demonstrated to facilitate treating tissue and, specifically,sealing tissue. With respect to mechanical clamping pressure for tissuesealing, for example, it has been found that pressures within the rangeof about 3 kg/cm² to about 16 kg/cm² help ensure formation of effectiveand consistent tissue seals. Other pressures within or outside thisrange may be utilized for treating tissue in a different manner and/orfor other purposes.

SUMMARY

As used herein, the term “distal” refers to the portion of theinstrument or component thereof that is being described that is furtherfrom a user, while the term “proximal” refers to the portion of theinstrument or component thereof that is being described that is closerto a user. Further, to the extent consistent, any of the aspectsdescribed herein may be used in conjunction with any of the otheraspects described herein.

Provided in accordance with aspects of the present disclosure is asurgical instrument including a housing, an elongated shaft extendingdistally from the housing, an end effector disposed at a distal end ofthe elongated shaft, an actuator operably coupled to the housing, anactuation assembly extending through the housing and the elongatedshaft, and a sensor module. The actuation assembly includes a spring, adistal end operably coupled to the end effector or a componentassociated therewith, and a proximal end operably coupled to theactuator such that actuation of the actuator manipulates the endeffector or deploys the component relative thereto. The sensor module isdisposed within the housing and configured to sense a property of thespring indicative of an amount the spring has been compressed. Thesensor module is further configured, based upon the sensed property, todetermine a condition of the end effector or a relative position of thecomponent.

In an aspect of the present disclosure, the end effector includes firstand second jaw members movable between an open position and a closedposition for grasping tissue therebetween. In such aspects, thecondition the sensor module is configured to determine is a clampingpressure applied to tissue grasped between the first and second jawmembers.

In another aspect of the present disclosure, the actuation assemblyincludes a jaw drive rod extending through the housing and the elongatedshaft. The jaw drive rod is operably coupled to the first and second jawmembers at a distal end of the jaw drive rod. The actuator is operablycoupled to a proximal end of the jaw drive rod via a force regulationmechanism including the spring.

In yet another aspect of the present disclosure, the first and secondjaw members are configured to supply electrosurgical energy to tissuegrasped therebetween to treat tissue.

In still another aspect of the present disclosure, the deployablecomponent includes a knife blade deployable relative to the end effectorfrom a retracted to an extended position. In such aspects, the conditionthe sensor module is configured to determine is an extent to which theknife blade has been deployed relative to the end effector.

In still yet another aspect of the present disclosure, the actuationassembly includes a link, a carriage, and the spring. The link isoperably coupled to the actuator and the carriage is operably coupledbetween the link and the knife blade such that actuation of the triggerdeploys the knife blade from the retracted position to the extendedposition against a bias of the spring.

In another aspect of the present disclosure, the sensor module includesone or more spring sensors and a processor. The spring sensor(s) isconfigured to sense the property of the spring indicative of the amountthe spring has been compressed and relay the sensed property to theprocessor to determine the condition of the end effector or the relativeposition of the component based upon the sensed property. In suchaspects, the spring sensor(s) may be configured to sense a change ininductance of the spring indicative of the amount the spring has beencompressed. Alternatively, the spring sensor(s) may be configured tosense a spacing between rungs of the spring indicative of the amount thespring has been compressed.

In still another aspect of the present disclosure, the sensor modulefurther includes a storage device configured to store data representinga relationship between the property of the spring indicative of theamount the spring has been compressed and the condition of the endeffector or the relative position of the component. The processor, insuch aspects, is configured to access the data to determine thecondition of the end effector or the relative position of the componentbased upon the sensed property. The data may be stored in the storagedevice as a look-up table.

In yet another aspect of the present disclosure, the sensor moduleincludes an output device configured to output an indicator based uponthe condition of the end effector or the relative position of thecomponent determined by the processor. The indicator may includeincludes an audible output, a visual output, and/or a tactile output.

Another surgical instrument provided in accordance with aspects of thepresent disclosure includes a movable handle movable from an initialposition to a compressed position, an end effector remote from themovable handle and movable from an open configuration to a closedconfiguration for grasping tissue, an actuation assembly including adistal end operably coupled to the end effector and a proximal end, aforce regulating mechanism including a spring and operably coupling themovable handle with the proximal end of the actuation assembly such thatmovement of the movable handle from the initial position to thecompressed position moves the end effector from the open configurationto the closed configuration, and a sensor module. The force regulatingmechanism is configured to regulate a clamping pressure applied totissue grasped by the end effector. The sensor module is configured tosense a property of the spring of the force regulating mechanismindicative of an amount the spring has been compressed and, based uponthe sensed property, determine the clamping pressure applied to tissue.

In an aspect of the present disclosure, the sensor module includes oneor more spring sensors and a processor. The spring sensor(s) isconfigured to sense the property of the spring indicative of the amountthe spring has been compressed and relay the sensed property to theprocessor to determine the clamping pressure applied to tissue basedupon the sensed property.

In another aspect of the present disclosure, the spring sensor(s) isconfigured to sense a change in inductance of the spring indicative ofthe amount the spring has been compressed. Alternatively, the springsensor(s) may be configured to sense a spacing between rungs of thespring indicative of the amount the spring has been compressed.

In yet another aspect of the present disclosure, the sensor modulefurther includes a storage device configured to store data representinga relationship between the property of the spring indicative of theamount the spring has been compressed and the clamping pressure appliedto tissue. The processor is configured to access this data to determinethe clamping pressure applied to tissue based upon the sensed property.The data may be stored in the storage device as a look-up table.

In still another aspect of the present disclosure, the sensor moduleincludes an output device configured to output an indicator based uponthe clamping pressure applied to tissue determined by the processor.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects and features of the present disclosure are describedherein with reference to the drawings, wherein like reference numeralsidentify similar or identical components, and wherein:

FIG. 1 is a perspective view of a surgical instrument configured for usein accordance with the present disclosure;

FIG. 2A is an enlarged perspective view of an end effector assembly ofthe surgical instrument of FIG. 1, wherein jaw members thereof aredisposed in an open configuration;

FIG. 2B is an enlarged perspective view of the end effector assembly ofthe surgical instrument of FIG. 1, wherein the jaw members thereof aredisposed in a closed configuration;

FIG. 3A is a side view of a proximal portion of the surgical instrumentof FIG. 1 with a portion of a housing removed to illustrate the internalcomponents thereof, wherein a movable handle is disposed in an initialposition corresponding to the open configuration of the jaw members;

FIG. 3B is a side view of the proximal portion of the surgicalinstrument of FIG. 1 with a portion of the housing removed to illustratethe internal components thereof, wherein the movable handle is disposedin an intermediate position corresponding to a partially-closedconfiguration of the jaw members;

FIG. 3C is a side view of the proximal portion of the surgicalinstrument of FIG. 1 with a portion of the housing removed to illustratethe internal components thereof, wherein the movable handle is disposedin a compressed position corresponding to the closed configuration ofthe jaw members;

FIG. 4 is a partial, side view of the proximal portion of a jawactuation mechanism of the surgical instrument of FIG. 1, illustrating aspring sensor provided in accordance with the present disclosure shownoperably coupled with the jaw actuation mechanism;

FIG. 5 is a partial, side view of the proximal portion of the jawactuation mechanism of the surgical instrument of FIG. 1, illustratinganother spring sensor provided in accordance with the present disclosureshown operably coupled with the jaw actuation mechanism; and

FIG. 6 is a schematic illustration of a robotic surgical systemconfigured for use in conjunction with aspects and features of thepresent disclosure.

DETAILED DESCRIPTION

Turning to FIG. 1, a surgical instrument 10 configured for use inaccordance with the present disclosure is shown generally including ahousing 12 that supports various actuators, e.g., a movable handle 22, atrigger 26, a rotation knob 28, and a switch 36, for remotelycontrolling an end effector assembly 14 through an elongated shaft 16.Although illustrated and described herein as an electrosurgical forcepsconfigured for use in laparoscopic or endoscopic surgical procedures,the aspects and features of the present disclosure are equallyapplicable for use with other surgical instruments configured for use intraditional open surgical procedures and/or laparoscopic or endoscopicsurgical procedures. For the purposes herein, instrument 10 is generallydescribed.

Housing 12 of instrument 10 is constructed of a first housing half 12 aand a second housing half 12 b. Housing halves 12 a, 12 b may beconstructed of sturdy plastic, or other suitable material, and may bejoined to one another by adhesives, ultrasonic welding, or othersuitable assembly process. Housing 12 supports a stationary handle 20, amovable handle 22, a trigger 26, and a rotation knob 28. Movable handle22, as detailed below, is operable to move jaw members 30, 32 of endeffector assembly 14 between an open configuration (FIG. 2A), whereinjaw members 30, 32 are disposed in spaced relation relative to oneanother, and a closed configuration (FIG. 2B), wherein jaw members 30,32 are approximated relative to one another. More specifically,compression of movable handle 22 towards stationary handle 20 serves tomove end effector assembly 14 to the closed configuration and return ofmovable handle 22 away from stationary handle 20 serves to move endeffector assembly 14 back to the open configuration. Trigger 26, as alsodetailed below, is operable to extend and retract a knife blade 56 (seeFIG. 2A) between jaw members 30, 32 when the end effector assembly 14 isin the closed configuration. Rotation knob 28 serves to rotate elongatedshaft 16 and end effector assembly 14 relative to housing 12.

To electrically control end effector assembly 14, housing 12 supports aswitch 36 thereon, which is operable to initiate and terminate thedelivery of electrosurgical energy to end effector assembly 14. Switch36 is in electrical communication with a source of electrosurgicalenergy such as electrosurgical generator 40. A cable 42 extends betweenhousing 12 and generator 40 and may include a connector (not shown)thereon such that instrument 10 may be selectively electrically coupledand decoupled from generator 40. In other embodiments, instrument 10 maybe configured as a battery-powered instrument wherein generator 40 ismounted on or within instrument 10.

Referring to FIGS. 2A and 2B, end effector assembly 14 includes firstand second jaw members 30, 32 mechanically coupled to the distal end ofelongated shaft 16 about a pivot pin 44. Jaw members 30, 32 areelectrically coupled to cable 42 and, thus, generator 40 (FIG. 1) viawires (not shown) extending through elongated shaft 16.Electrically-conductive plates 48, 50 of jaw members 30, 32,respectively are electrically coupled to opposite terminals, e.g.,positive (+) and negative (−) terminals, associated with generator 40.Thus, bipolar energy may be conducted through tissue grasped betweenplates 48, 50 of jaw members 30, 32, respectively, to treat tissue.Alternatively, end effector assembly 14 may be configured for deliveringmonopolar energy to the tissue for use in connection with a return pad(not shown) remotely positioned on the patient. Other forms of energy,e.g., ultrasonic, microwave, thermal, light, etc. may additionally oralternatively be used to facilitate tissue treatment.

As noted above, jaw members 30, 32 are pivoted about pivot pin 44 andrelative to elongated shaft 16 between the open configuration (FIG. 2A)and the closed configuration (FIG. 2B). In the closed configuration ofend effector assembly 14 (FIG. 2B), electrically-conductive plates 48,50 of jaw members 30, 32 provide a clamping pressure to the tissuegrasped therebetween. Also, in the closed configuration, a minimum gapdistance “G” may be maintained between electrically-conductive plates48, 50 by one or more stop members 54 disposed on either or bothelectrically-conductive plates 48, 50.

Referring to FIGS. 3A-3C, in conjunction with FIGS. 2A and 2B, a driveassembly 70 operably couples movable handle 22 with end effectorassembly 14 such that, as noted above, movable handle 22 is operable tomove jaw members 30, 32 of end effector assembly 14 between the openconfiguration (FIG. 2A) and the closed configuration (FIG. 2B). Driveassembly 70 includes a jaw drive rod 80 slidably disposed withinelongated shaft 16. The distal end of jaw drive rod 80 is operablycoupled to jaw members 30, 32, e.g., via a pin (not shown) associatedwith jaw drive rod 80 and extending through oppositely-angled slots (notshown) defined within proximal flanges (not shown) of jaw members 30,32, such that proximal sliding of jaw drive rod 80 through elongatedshaft 16 moves end effector assembly 14 from the open configuration tothe closed configuration. However, the opposite configuration is alsocontemplated, as are other mechanisms for operably coupling jaw driverod 80 with jaw members 30, 32.

The proximal end of jaw drive rod 80 extends into housing 12. Driveassembly 70 further includes a proximal stop ring 81 fixedly engagedabout jaw drive rod 80 within housing 12, a distal stop ring 82 fixedlyengaged about jaw drive rod 80 within housing 12, and a mandrel 84slidably disposed about jaw drive rod 80 within housing 12 andpositioned between proximal and distal stop rings 81, 82, respectively.A spring 86 of drive assembly 70 is disposed about jaw drive rod 80 andpositioned between proximal stop ring 81 and mandrel 84. Spring 86biases mandrel 84 distally along jaw drive rod 80 into contact withdistal stop ring 82, which inhibits further distal sliding of mandrel 84about jaw drive rod 80.

Movable handle 22 is pivotably coupled within housing 12 via a pivot pin75 and is operably coupled to jaw drive rod 80 by way of mandrel 84 suchthat movable handle 22 may be manipulated to impart longitudinal motionto jaw drive rod 80. As noted above, longitudinal movement of jaw driverod 80, in turn, moves end effector assembly 14 between the open andclosed configurations (FIGS. 2A and 2B, respectively). Morespecifically, a portion of movable handle 22 is operably retainedbetween distal and proximal rims 84 a, 84 b, respectively, of mandrel 84such that pivoting of movable handle 22 towards stationary handle 20urges mandrel 84 proximally through housing 12 and elongated shaft 16and such that pivoting of movable handle 22 away from stationary handle20 urges mandrel 84 distally through housing 12. Distal longitudinalmotion of mandrel 84, in response to pivoting of movable handle 22 awayfrom stationary handle 20, is transmitted directly into distaltranslation of jaw drive rod 80 through housing 12 and elongated shaft16 due to the abutment mandrel 84 with distal stop ring 82. As notedabove, such movement of jaw drive rod 80 results in the return of jawmembers 30, 32 towards the open condition (FIG. 2A).

Proximal longitudinal motion of mandrel 84, in response to pivoting ofmovable handle 22 towards stationary handle 20, initially effects acorresponding proximal motion of jaw drive rod 80 through housing 12 andelongated shaft 16 to thereby move jaw members 30, 32 towards the closedcondition (FIG. 2B). During this initial movement, jaw members 30, 32meet minimal resistance as they move towards the closed condition (FIG.2B) and, thus, spring 86 remains in its initial condition, e.g., aninitial pre-compressed condition or, in some embodiments, anun-compressed condition. However, once jaw members 30, 32 are closedabout tissue, where mechanical stops (not explicitly shown) associatedwith end effector assembly 14 or the distal end of jaw drive rod 80 havebeen reached, and/or where jaw members 30, 32 otherwise meet sufficientresistance, further pivoting of movable handle 22 towards stationaryhandle 20 translates mandrel 84 proximally through housing 12 relativeto jaw drive rod 80, rather than moving jaw drive rod 80 in conjunctiontherewith. In order to permit this relative sliding between mandrel 84and jaw drive rod 80, spring 86 is compressed. The compression of spring86 serves as a force-regulator to ensure than an appropriate clampingpressure is applied to tissue grasped between plates 48, 50 of jawmembers 30, 32. For tissue sealing, for example, this pressure may bewithin the range of about 3 kg/cm² to about 16 kg/cm²; however, othersuitable pressures may also be provided.

As noted above, the compression of spring 86 enables regulation of theclamping pressure applied to tissue grasped between plates 48, 50 of jawmembers 30, 32. In fact, the amount spring 86 is compressed isindicative of the clamping pressure applied to tissue. Accordingly, asdetailed below, a sensor module 200 is incorporated into instrument 10to determine the amount of compression of spring 86 and, based upon thatinformation, determine the clamping pressure applied to tissue.

Referring to FIG. 4, sensor module 200 is mounted within housing 12(FIGS. 3A-3C) adjacent spring 86 and generally includes a spring sensor202, a storage device 210, a CPU 220 including a memory 222 and aprocessor 224, and an output device 230. Spring sensor 202 iselectrically coupled to a first end of spring 86 via lead wire 204 andto a second end of spring 86 via lead wire 206 and includes internalcomponents (not explicitly shown) configured to measure a change ininductance of spring 86. Since the inductance of a spring changes as thespring is compressed, measuring the change in inductance of spring 86can be used to determine the extent to which spring 86 has beencompressed. Sensors suitable for this purpose include those detailed inIntl. Appln. Pub. No. WO 2008/090338, filed on Jan. 23, 2008, the entirecontents of which are hereby incorporated herein by reference. Thechange in inductance sensed by spring sensor 202 is relayed to CPU 220.

The relationship between the change in inductance of spring 86 and theamount of compression of spring 86 can be determined empirically and/orexperimentally. Likewise, the relationship between the amount ofcompression of spring 86 and the clamping pressure applied to tissue canbe determined, empirically and/or experimentally. Putting this datatogether, the relationship between the change in inductance of spring 86and the clamping pressure applied to tissue can be determined.Alternatively, the relationship between the change in inductance ofspring 86 and the clamping pressure applied to tissue can be determined,empirically and/or experimentally, without the intermediate step ofdetermining the relationships of these metrics with the compression ofspring 86. In either instance, such relationship data can be stored, forexample, as a look-up table in storage device 210 of sensor module 200.

Storage device 210 of sensor module 200 may include any suitablecomponent(s) operable for storing information, e.g., the look-up tableincluding information indicating the relationship between the change ininductance of spring 86, the amount of compression of spring 86, and/orthe resultant clamping pressure applied to tissue, such as, for example,a magnetic disk, flash memory, optical disk, or other suitable datastorage device.

CPU 220 of sensor module 220 is configured to receive the change ininductance sensed by spring sensor 202. Memory 222 of CPU 220 mayinclude any computer memory, e.g., RAM or ROM, mass storage media,removable storage media, combinations thereof, or any other suitablecomputer-readable storage medium, storing instructions for causingprocessor 224 to execute particular functions, e.g., to access thelook-up table stored in storage device 210 of sensor module 200 anddetermine the clamping pressure corresponding to the change ininductance sensed by spring sensor 202 (directly or by way of the amountof compression of spring 86). Processor 224 may further be configured todetermine whether the corresponding clamping pressure is within anappropriate clamping pressure range. The appropriate clamping pressurerange may also be stored in storage device 210 and accessible byprocessor 224 for comparison with the determined clamping pressure.

In embodiments where processor 224 determines whether the determinedclamping pressure is within the appropriate clamping pressure range,processor 224 may further be configured to direct output device 230 toprovide a notification indicating whether the determined clampingpressure is or is not within the appropriate clamping pressure range.For example, output device 230 may emit an audible tone, activate avisual indicator, provide a tactile response, etc. when the determinedclamping pressure is within the appropriate clamping pressure range.Once alerted to the fact that an appropriate clamping pressure has beenapplied, the surgeon can confidently initiate the supply ofelectrosurgical energy to end effector assembly 14 (FIGS. 2A and 2B) totreat the grasped tissue. Output device 230 may, alternatively oradditionally, be configured to communicate with generator 40 (FIG. 1)such that the supply of electrosurgical energy may automatically beinitiated upon reaching a suitable clamping pressure and/or such that anappropriate energy-delivery algorithm is utilized based upon theclamping pressure or clamping pressure range determined. In embodimentswhere processor 224 does not determine whether the clamping pressure iswithin the appropriate clamping pressure range, processor 224 may beconfigured to direct output device 230 to provide a notificationindicating the particular clamping pressure that has been determined.Output 230, in such instances, for example, may transmit suitableinformation to generator 40 (FIG. 1) to enable display of the clampingpressure on the display screen of generator 40 (FIG. 1) or to inhibitthe supply of electrosurgical energy until an appropriate clampingpressure is applied or until an override is input to generator 40 (FIG.1).

As detailed above, sensor module 200 enables a surgeon to be readilyapprised of the clamping pressure applied to tissue and/or whether theclamping pressure is within an appropriate clamping pressure range. Byproviding a sensor module 200 capable of determining the clampingpressure applied to tissue based upon a condition of spring 86, which isdisposed in housing 12 and remote from end effector assembly 14, theneed for providing such sensors in or around end effector assembly 14,wherein spatial, temperature, environmental, and other considerationsresult in design challenges and increased manufacturing costs, isobviated.

As an alternative to spring sensor 202 measuring a change in inductanceto determine the condition of spring 86, spring sensor 202 may beconfigured as a hall-effect sensor configured to determine the conditionof spring 86 and, based thereon, determine the clamping pressure appliedto tissue, similarly as detailed above.

Further, in addition to sensor module 200 determining the clampingpressure applied to tissue, sensor module 200 and/or additional sensors(not explicitly shown) may be utilized, in conjunction with thedetermined clamping pressure applied, to provide additional informationto generator 40 (FIG. 1) for determining an appropriate energy-deliveryalgorithm to be utilized. For example, the thickness of grasped tissuemay be determined by sensor module 200 (or other suitable sensor) andthe impedance of grasped tissue may be determined by impedance sensors(not shown) within generator 40. With clamping pressure, tissuethickness, and tissue impedance measurements, a look-up table or othersuitable component(s) of storage device 210 and/or generator 40 (FIG.1), for storing empirical and/experimental data of such measurements,may be consulted to determine the appropriate energy-delivery algorithmto be utilized based upon these three measurements. Notably, sensormodule 200 and/or the additional sensors (not explicitly shown) need notcease operation once the supply of electrosurgical energy has beeninitiated. More specifically, since tissue properties change during theapplication of electrosurgical energy thereto, feedback, as determinedby a change in clamping pressure detected by sensor module 200, a changein tissue thickness detected by sensor module 200 or other suitablesensor (not shown), and/or a change in tissue impedance, may be utilizedto ensure that an appropriate energy-deliver algorithm is utilizedthroughout the entire tissue-treatment process.

Turning to FIG. 5, another embodiment of a sensor module 300 provided inaccordance with the present disclosure is shown configured for use withspring 86 for determining the compression thereof and, based upon such adetermination, the clamping pressure applied to tissue. Sensor module300 is similar to sensor module 200 (FIG. 4) in that it includes astorage device 310, a CPU 320 including a memory 322, a processor 224,and an output device 330. These common components are similar to thoseof sensor module 200 (FIG. 4) and, thus, will not be detailed again toavoid unnecessary repetition. Rather, only differences between sensormodule 300 and sensor module 200 (FIG. 4) will be detailed below.

Sensor module 300 differs from sensor module 200 (FIG. 4) in that,rather than sensing the change in inductance of spring 86, sensor module300 includes one or more optical sensors 302, e.g., one or more opticalencoder sensors, configured to sense a spacing between the rungs ofspring 86. The one or more optical sensors 302 may be configured tosense the spacing between any or all pairs of adjacent rungs of spring86 and determine an average spacing therebetween. Similarly as withinductance, the average spacing between the rungs of spring 86 can becorrelated to an amount of compression of spring 86. As noted above, theamount of compression of spring 86, in turn, can be utilized todetermine the clamping pressure applied to tissue based on data obtainedempirically or via experimentation. Sensor module 300 may otherwise beused similarly as detailed above with respect to sensor module 200 (FIG.4).

With additional reference to FIGS. 3A-3C, sensor module 300 (and/orsensor module 200 (FIG. 4)) may further be configured such that one ormore of sensors 302 is capable of sensing the position of movable handle22. This may be accomplished by sensing the position of jaw drive rod 80or a component fixed thereto, e.g., proximal stop ring 81. The positionof movable handle 22 may be communicated to generator 40 (FIG. 1) suchthat the supply of electrosurgical energy from generator 40 (FIG. 1) maybe initiated in accordance with the position of movable handle 22, e.g.,when movable handle 22 is sufficiently compressed relative to fixedhandle 20. Additionally or alternatively, the position of movable handle22 may be utilized, in connection with the determined clamping pressureand/or other measurements, to further refine the energy-deliveryalgorithm used, e.g., based upon whether a slow-jaw-closure technique isbeing utilized during tissue treatment.

Referring to FIGS. 3A-3C, trigger 26 may be manipulated to impartlongitudinal motion to knife blade 56 to advance knife blade 56 throughknife channel(s) 58 defined within one or both of the jaw members 30, 32(see FIG. 2A). Trigger 26 is pivotally supported in housing 12 via apivot pin 92 and is operably coupled to knife blade 56 (FIG. 2A) by aconnection mechanism 94. Connection mechanism 94 includes a link 96 anda carriage 98 having the proximal end of knife blade 56 (FIG. 2A)engaged therein. A spring 99 is disposed between the distal end ofhousing 12 and carriage 98 so as to bias carriage 98 proximally, therebybiasing knife blade 56 towards a retracted position, wherein knife blade56 is positioned proximally of jaw members 30, 32 (see FIG. 2A), andtrigger 26 proximally towards an un-actuated position. Upon actuation oftrigger 26, e.g., upon pivoting of trigger 26 towards movable handle 22,linkage 96 is pulled distally to thereby urge carriage 98 distallythrough housing 12. Distal urging of carriage 98, in turn, compressesspring 99 and advances knife blade 56 distally between jaw members 30,32 (see FIG. 2A) to cut tissue grasped therebetween.

With respect to deployment of knife blade 56 via actuation of trigger26, due to the above-detailed configuration, the amount of compressionof spring 99 is related to the extent to which knife blade 56 has beendeployed. Accordingly, as with sensor modules 200, 300 and spring 86(FIGS. 4 and 5), a sensor module similar to sensor modules 200, 300(FIGS. 4 and 5) may be utilized in connection with spring 99 to indicateto a surgeon the extent to which knife blade 56 has been deployed. Infact, sensor modules similar to sensor modules 200, 300 (FIGS. 4 and 5)may be provided in accordance with the present disclosure for use with asuitable spring of a surgical instrument to indicate the position and/orforce associated with an end effector assembly and/or deployablecomponent of the surgical instrument.

The above-detailed aspects and features of the present disclosure may beconfigured to work with robotic surgical systems and what is commonlyreferred to as “Telesurgery.” Such systems employ various roboticelements to assist the surgeon and allow remote operation (or partialremote operation) of surgical instrumentation. Various robotic arms,gears, cams, pulleys, electric and mechanical motors, etc. may beemployed for this purpose and may be designed with a robotic surgicalsystem to assist the surgeon during the course of an operation ortreatment. Such robotic systems may include remotely steerable systems,automatically flexible surgical systems, remotely flexible surgicalsystems, remotely articulating surgical systems, wireless surgicalsystems, modular or selectively configurable remotely operated surgicalsystems, etc.

The robotic surgical systems may be employed with one or more consolesthat are next to the operating theater or located in a remote location.In this instance, one team of surgeons or nurses may prep the patientfor surgery and configure the robotic surgical system with one or moreof the instruments disclosed herein while another surgeon (or group ofsurgeons) remotely control the instruments via the robotic surgicalsystem. As can be appreciated, a highly skilled surgeon may performmultiple operations in multiple locations without leaving his/her remoteconsole which can be both economically advantageous and a benefit to thepatient or a series of patients.

The robotic arms of the surgical system are typically coupled to a pairof master handles by a controller. The handles can be moved by thesurgeon to produce a corresponding movement of the working ends of anytype of surgical instrument (e.g., end effectors, graspers, knifes,scissors, etc.) which may complement the use of one or more of theembodiments described herein. The movement of the master handles may bescaled so that the working ends have a corresponding movement that isdifferent, smaller or larger, than the movement performed by theoperating hands of the surgeon. The scale factor or gearing ratio may beadjustable so that the operator can control the resolution of theworking ends of the surgical instrument(s).

The master handles may include various sensors to provide feedback tothe surgeon relating to various tissue parameters or conditions, e.g.,tissue resistance due to manipulation, cutting or otherwise treating,pressure by the instrument onto the tissue, tissue temperature, tissueimpedance, etc. As can be appreciated, such sensors provide the surgeonwith enhanced tactile feedback simulating actual operating conditions.The master handles may also include a variety of different actuators fordelicate tissue manipulation or treatment further enhancing thesurgeon's ability to mimic actual operating conditions.

Turning to FIG. 6, a medical work station is shown generally as workstation 1000 and generally may include a plurality of robot arms 1002,1003; a control device 1004; and an operating console 1005 coupled withcontrol device 1004. Operating console 1005 may include a display device1006, which may be set up in particular to display three-dimensionalimages; and manual input devices 1007, 1008, by means of which a surgeonmay be able to telemanipulate robot arms 1002, 1003 in a first operatingmode.

Each of the robot arms 1002, 1003 may include a plurality of members,which are connected through joints, and an attaching device 1009, 1011,to which may be attached, for example, a surgical tool “ST” supportingan end effector 1100, in accordance with any one of several embodimentsdisclosed herein, as will be described in greater detail below.

Robot arms 1002, 1003 may be driven by electric drives (not shown) thatare connected to control device 1004. Control device 1004 (e.g., acomputer) may be set up to activate the drives, in particular by meansof a computer program, in such a way that robot arms 1002, 1003, theirattaching devices 1009, 1011 and thus the surgical tool (including endeffector 1100) execute a desired movement according to a movementdefined by means of manual input devices 1007, 1008. Control device 1004may also be set up in such a way that it regulates the movement of robotarms 1002, 1003 and/or of the drives.

Medical work station 1000 may be configured for use on a patient 1013lying on a patient table 1012 to be treated in a minimally invasivemanner by means of end effector 1100. Medical work station 1000 may alsoinclude more than two robot arms 1002, 1003, the additional robot armslikewise being connected to control device 1004 and beingtelemanipulatable by means of operating console 1005. A medicalinstrument or surgical tool (including an end effector 1100) may also beattached to the additional robot arm. Medical work station 1000 mayinclude a database 1014, in particular coupled to with control device1004, in which are stored, for example, pre-operative data frompatient/living being 1013 and/or anatomical atlases.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely as examplesof particular embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appended hereto.

Although the foregoing disclosure has been described in some detail byway of illustration and example, for purposes of clarity orunderstanding, it will be obvious that certain changes and modificationsmay be practiced within the scope of the appended claims.

What is claimed is:
 1. A surgical instrument, comprising: a housing; anelongated shaft extending distally from the housing; an end effectordisposed at a distal end of the elongated shaft; an actuator operablycoupled to the housing; an actuation assembly extending through thehousing and the elongated shaft, the actuation assembly including aspring and a distal end operably coupled to the end effector assembly ora component associated therewith and a proximal end operably coupled tothe actuator such that actuation of the actuator manipulates the endeffector assembly or deploys the component relative thereto; and asensor module disposed within the housing and configured to sense aproperty of the spring indicative of an amount the spring has beencompressed, the sensor module further configured, based upon the sensedproperty, to determine a condition of the end effector or the relativeposition of the component.
 2. The surgical instrument according to claim1, wherein the end effector includes first and second jaw membersmovable between an open position and a closed position for graspingtissue therebetween, and wherein the condition the sensor module isconfigured to determine is a clamping pressure applied to tissue graspedbetween the first and second jaw members.
 3. The surgical instrumentaccording to claim 2, wherein the actuation assembly includes a jawdrive rod extending through the housing and the elongated shaft, andoperably coupled to the first and second jaw members at a distal end ofthe jaw drive rod, and wherein the actuator is operably coupled to aproximal end of the jaw drive rod via a force regulation mechanismincluding the spring.
 4. The surgical instrument according to claim 2,wherein the first and second jaw members are configured to supplyelectrosurgical energy to tissue grasped therebetween to treat tissue.5. The surgical instrument according to claim 1, wherein the componentincludes a knife blade deployable relative to the end effector from aretracted to an extended position, and wherein the condition the sensormodule is configured to determine is an extent to which the knife bladehas been deployed relative to the end effector.
 6. The surgicalinstrument according to claim 5, wherein the actuation assembly includesa link, a carriage, and the spring, the link operably coupled to theactuator and the carriage operably coupled between the link and theknife blade such that actuation of the trigger deploys the knife bladefrom the retracted position to the extended position against a bias ofthe spring.
 7. The surgical instrument according to claim 1, wherein thesensor module includes at least one spring sensor and a processor, theat least one spring sensor configured to sense the property of thespring indicative of the amount the spring has been compressed and relaythe sensed property to the processor to determine the condition of theend effector or the relative position of the component based upon thesensed property.
 8. The surgical instrument according to claim 7,wherein the at least one spring sensor is configured to sense a changein inductance of the spring indicative of the amount the spring has beencompressed.
 9. The surgical instrument according to claim 7, wherein theat least one spring sensor is configured to sense a spacing betweenrungs of the spring indicative of the amount the spring has beencompressed.
 10. The surgical instrument according to claim 7, whereinthe sensor module further includes a storage device configured to storedata representing a relationship between the property of the springindicative of the amount the spring has been compressed and thecondition of the end effector or the relative position of the component,the processor configured to access the data to determine the conditionof the end effector or the relative position of the component based uponthe sensed property.
 11. The surgical instrument according to claim 10,wherein the data is stored in the storage device as a look-up table. 12.The surgical instrument according to claim 7, wherein the sensor moduleincludes an output device configured to output an indicator based uponthe condition of the end effector or the relative position of thecomponent determined by the processor.
 13. The surgical instrumentaccording to claim 12, wherein the indicator includes at least one of anaudible output, a visual output, or a tactile output.
 14. A surgicalinstrument, comprising: a movable handle movable from an initialposition to a compressed position; an end effector remote from themovable handle, the end effector movable from an open configuration to aclosed configuration for grasping tissue; an actuation assemblyincluding a distal end operably coupled to the end effector and aproximal end; a force regulating mechanism including a spring, the forceregulating mechanism operably coupling the movable handle with theproximal end of the actuation assembly such that movement of the movablehandle from the initial position to the compressed position moves theend effector from the open configuration to the closed configuration,the force regulating mechanism configured to regulate a clampingpressure applied to tissue grasped by the end effector; and a sensormodule configured to sense a property of the spring of the forceregulating mechanism indicative of an amount the spring has beencompressed and, based upon the sensed property, determine the clampingpressure applied to tissue.
 15. The surgical instrument according toclaim 14, wherein the sensor module includes at least one spring sensorand a processor, the at least one spring sensor configured to sense theproperty of the spring indicative of the amount the spring has beencompressed and relay the sensed property to the processor to determinethe clamping pressure applied to tissue based upon the sensed property.16. The surgical instrument according to claim 15, wherein the at leastone spring sensor is configured to sense a change in inductance of thespring indicative of the amount the spring has been compressed.
 17. Thesurgical instrument according to claim 15, wherein the at least onespring sensor is configured to sense a spacing between rungs of thespring indicative of the amount the spring has been compressed.
 18. Thesurgical instrument according to claim 15, wherein the sensor modulefurther includes a storage device configured to store data representinga relationship between the property of the spring indicative of theamount the spring has been compressed and the clamping pressure appliedto tissue, the processor configured to access the data to determine theclamping pressure applied to tissue based upon the sensed property. 19.The surgical instrument according to claim 18, wherein the data isstored in the storage device as a look-up table.
 20. The surgicalinstrument according to claim 15, wherein the sensor module includes anoutput device configured to output an indicator based upon the clampingpressure applied to tissue determined by the processor.